1. Field of the Invention
The present invention relates to a print position indicator which indicates the position at which a print head will next print on a recording medium. More specifically, the present invention relates to a print position indicator which is coupleable to and uncoupleable from a print head so as to continue to indicate the next print position, even when the print head is no longer adjacent the next print position.
2. Description of the Related Art
In typewriters and printers (both hereinafter referred to as "printers") of the type where the print head rather than the recording medium moves, conventional print position indicators are ordinarily fixed to the print head. As the print head travels across the recording medium, the print position indicator moves with it so as to continuously indicate where the print head will next print.
Fixing the print position indicator to the print head, however, is disadvantageous for printers of a more recent type in which the print head is not always adjacent to the next print position. For example, non-impact type printers, such as ink jet printers, print by ejecting heated ink droplets out of ink nozzles in patterns that form desired letters and symbols onto the recording medium. These ink nozzles dry out and/or clog if exposed to air without printing. To prevent such drying out, a capping mechanism is provided at a "home" position, usually the left-most carriage position of the print head, and the print head is periodically returned to the capping mechanism when more than 5 seconds elapse since printing has occurred. But, because the position indicator is fixed to the print head, it also moves to the capping mechanism giving an erroneous indication of the next print position.
Even more recently, some ink jet printers have been developed which store a certain number of input characters before printing any of them and then print all the stored characters at once. Since the print head does not move until the characters are printed, print position indicators that are fixed to the print head again give an erroneous indication of the next print position. As a result, large numbers of characters may be printed without their position being indicated.
Thus, there is a need for a position indicator that indicates the print position even when the print head is not adjacent the next print position. There is also a need for a position indicator that permits the print head to stay at the home position while indicating the print position of plural characters that have been input but not yet printed.